Maggie, first let me apologize for taking so long to respond to your
post.  I have not had the time to properly address your comments and
questions.  I want to also add that I have tried to rearrange and group
the questions together in such a way as to answer them thoroughly but
not be redundant.  I have NOT changed them, but rather cut and pasted
so that they are your words.  (BIG, I apologize to you for the length
of the post.)
 
Obviously I am not Bob, but I may be able to shed a little insight on
this.  I have NOT seen the pictures as I did not follow the links, so
the information I am sharing is based on my personal experience.  First
I will give you my qualifications and then my response.
 
On Fri, 11 Jul 2003 Maggie <[log in to unmask]> said:
>Perhaps there is someone on this list who has at least a master's degree
>in anthropology or biology who can help me out.  I would truly like to
>know if anyone has indeed mapped out functions of the brain.
 
In my doctoral program I have been involved in the mapping of the
auditory areas of the brain.  Due to my specific interest in audition,
the areas we examined were all related to hearing.  That does not mean
that there were not other areas of the brain designed to do other
things, only that the areas we looked at were related to hearing.
 
>Ferrets are animals built for detecting scents--nearly a third of the
>skull is dedicated to detect odor (orange region), while a large
>portion of the brain is used to process olfactory signals (blue region).
 
This is known to be true.  Ferrets use their sense of smell much more
than they do their vision, for example.  All polecats use scent to
communicate.  Due to the ability of the ferret brain to decipher so many
odors and the use of odors to members of the mustelid family, we would
expect the ferret to have a highly developed olfactory region.
 
>Ok, the orange area is sinus cavities, and ferrets use more of their
>brain for smelling than other animals.  Is this correct?  The orange
>area is sinus cavity and the blue area the brain cavity?
 
Two questions.  I don"t know if ferrets use more of their brains for
interpreting smells than other animals do, but they certainly use more
of their brains for interpreting odor than humans.
 
>Who did the studies that show so much of the ferret's brain is tied into
>a SINGLE function?  Is this all brain mass, or are the orange regions
>simple the sinus cavities?  And if so, why make it seem particularly
>special in ferrets?  I mean, how much of our cranial cavities are tied
>up to sinuses?
 
Based on the description that *nearly a third of the skull is dedicated
to detect odor,* it would not be unreasonable to interpret that statement
to mean that the size of the sinuses are about one-third the size of the
skull.  If you look at any diagram of the ferret"s skull, you will see
this is true.
 
Therefore, I would conclude that the orange areas ARE sinus cavities.
We have them, too, in the skull.  They are lined with receptors that
send the signal to the brain, where it is *processed* (blue regions),
or identified and interpreted.  IF the orange is areas of the brain that
are used to detect odor, it is still reasonable to expect the color and
regions to be different from the color and regions used to identify and
interpret the odor.
 
Based on the description that *a large portion of the brain is used to
process olfactory signals,* it would not be unreasonable to interpret
that statement to mean that the portion of the brain devoted to
interpreting the meaning of those olfactory signals is large.  From what
we know about odors being important to ferrets, it follows that they
should be able to detect and differentiate quite a few subtle differences
in odor that other species who do NOT have such large processing areas in
the brain cannot.  Therefore, I would conclude that the ferret uses a
great deal of its brain to identify and interpret odors it detects.
 
>Who did the studies that show so much of the ferret's brain is tied
>into a SINGLE function?
   AND (later)
>But I do want to know what documentation you have to support "your"
>ideas here.
 
While I cannot tell you WHO did the studies, I can tell you how you can
find out for yourself.  There are many search engines on the net that
can be used to find articles from peer-reviewed journals.  When I did a
Medline search on Friday, I got more than 3000 hits on the search word
*ferret.*  To find out how to use Medline, contact me.
 
>How can you say the brain is geared towards olfactory signals while
>leaving out so much else it does?  How can you justify painting the area
>of the brain one color and telling us it is used basically for the sense
>of smell.
 
The mapping of the brain is done by applying electrodes to certain
locations of the head, whether it is an animal or a human (just another
animal!).  When an individual has an EEG, the electrodes are placed all
over the head in a specific arrangement to record the best response from
the brain to certain stimuli.  The stimulus we use to study hearing is
sound, to study olfaction (smell), you would use scents.  The electrodes
detect responses to the stimuli that are then sent to the computer for
analysis.  A color scale, also generated by the computer, is used to
indicate areas of greater or lesser response to the stimulus.  The areas
of response show up based on that color.  That is the simple explanation.
For more, contact me.
 
>Just because an animal has a stronger sense of smell than we do doesn't
>mean that its brain it locked into that sense alone.
 
No, it does not mean it is locked into that sense alone.  In a series of
posts Bob has tried to address much of the individual senses and issues
related to ferrets.  Each individual post appears to me to be related
primarily to the specific topic mentioned.  In this case it was smell.
Therefore, I would expect that the area on which he focused in this post
would be smell and that all comments would be viewed in that light.
 
I hope this has helped shed a little light on the way info is gathered
and the post itself.  I do not have any special knowledge of ferret
olfaction.  As I said before, this is based on my personal experience
and interpretation of the post.
 
renee :)
[Posted in FML issue 4224]